Melanotaeniidae

Melanotaeniidae is a family of small, brightly colored fish native to freshwater habitats in Australia and New Guinea. The family includes approximately 30 species, which are commonly known as rainbowfish or melano. They are characterized by their vibrant colors, which are produced by iridophores and chromatophores, and their ability to change color in response to environmental cues. Melanotaeniidae are popular among aquarium enthusiasts due to their striking appearance and relatively easy care requirements.

The family is divided into two subfamilies: Melanotaeniinae and Paracheilodontinae. Melanotaeniinae includes the most well-known species, such as the blue melano (Melanotaenia fluviatilis) and the red melano (Melanotaenia splendida). These species are typically found in slow-moving rivers and streams, where they feed on small invertebrates and plant material. Paracheilodontinae includes species that are less commonly kept in aquariums, such as the black melano (Paracheilodus melanopus).

Melanotaeniidae are generally small, with most species reaching lengths of 5-10 centimeters. They have a laterally compressed body, with a rounded head and a long, forked tail. Their scales are cycloid, and they have a single dorsal fin, a single anal fin, and a continuous lateral line. Their coloration is highly variable, with many species exhibiting sexual dimorphism, where males and females have different color patterns.

Melanotaeniidae are generally peaceful fish, but they can be territorial within their aquarium. They require a well-planted aquarium with plenty of hiding places, as they are shy and prefer to hide during the day. They are omnivorous, feeding on a variety of foods, including algae, insects, and small crustaceans. Melanotaeniidae are relatively hardy fish, but they require specific water parameters to thrive. They prefer soft, slightly acidic water with a temperature range of 22-28 degrees Celsius.